# Relationship history for MSHA mine 4607087

Current hierarchy: **Alexander Building & Development Co & Ambrec Corp → Allied Mining Company → Mine #1**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Alexander Building & Development Company → Mine #1; 1986-03-01 to 1986-09-30; source msha-controller-operator-history
- **controller_controls_mine:** Alexander Dave Et Al → Mine #1; 1986-03-01 to 1986-09-30; source msha-controller-operator-history
- **controller_controls_operator:** Alexander Dave Et Al → Alexander Building & Development Company; 1986-03-01 to 1986-09-30; source msha-controller-operator-history
- **operator_operates_mine:** Allied Mining Company → Mine #1; 1986-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Alexander Building & Development Co & Ambrec Corp → Mine #1; 1986-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Alexander Building & Development Co & Ambrec Corp → Allied Mining Company; 1986-10-01 to current/open; source msha-controller-operator-history